Lap Joint Dissimilar Welding of Aluminium AA6061 and Galvanized Iron Using TIG Welding

• Main Authors: L. H., Shah, U. K., Mohamad, K. I., Yaakob, A. R., Razali, M., Ishak
• Format: Article
• Language: English
• Published: Faculty Mechanical Engineering, UMP 2016
• Subjects: TJ Mechanical engineering and machinery
• Online Access: http://umpir.ump.edu.my/id/eprint/14435/1/Lap%20Joint%20Dissimilar%20Welding%20of%20Aluminium%20AA6061%20and%20Galvanized%20Iron%20Using%20TIG%20Welding.pdf; http://umpir.ump.edu.my/id/eprint/14435/; http://dx.doi.org/10.15282/jmes.10.1.2016.6.0174

In this paper, aluminium AA6061-O and galvanized iron were lap-joined using tungsten inert gas (TIG) welding. The experiments were conducted using Si-rich filler metals ER4043 (Si 5 wt.%) and ER4047 (Si 12 wt.%). The mechanical properties and the microstructure of the samples were analysed using dye penetrant non-destructive tests (NDT), optical microscope observation and shear tests. All samples showed good quality joints, with Al-GI specimens showing better quality. Through optical microscope observation, the intermetallic compounds (IMC) of specimens using ER4043 fillers show a thin IMC layer ranging from 4 µm to 7 µm, compared to ER4047 samples which ranged between 20 µm and 40 µm. The shear tests show that the GI-Al group fractured at the IMC layer, while the Al-GI group fractured at the FZ-HAZ aluminium matrix. The highest shear strength value obtained was 89.82 MPa and 76.59 MPa for the Al-GI and GI-Al positions, respectively. It can be concluded that the GI-Al (galvanized iron on top and aluminium at the bottom) configuration with filler type ER4043 (Si 5 wt.%) has the optimum mechanical properties with a thin IMC layer and tensile strength of 76.59 MPa.